Has anyone ever made a true analog sampler? I was reading the recent posts under the Korg DSS-1 in which one user declared it to be analog and several others rightly explained it is hybrid at best. The DSS-1 stores samples (and modeled harmonics and hand-drawn wave forms) as PCM samples, which are digital, which makes the oscillators digital in nature. Every other sampler I look at, no matter how analog the signal path, digitizes the samples in a certain number of bits even if the waveforms are captured analogically. Is there any sampler that stores actual analog waves and plays them back directly as analog signals? The only one I can think of is the Mellotron, which uses the actual analog recordings stored on strips of magnetic tape. Is there any sampler that does this more conveniently in circuitry? Even an experimental one that never went into production? Has any sampler ever been based on wire recording? (The predecessor of magnetic tape.) I could imagine a device much like a piano with linear array of wires, but operating like the Mellotron with moving read/write heads, or perhaps the wires spooled endlessly on a drum. I'm rather surprised the Mellotron designers didn't go with this technology rather than the much more fragile magnetic tape. Tape recording is much higher density, at least with later technology, but wire is hardier and would last much longer under continuous use.

More central to the proposition, the only difference I can see between analog and digital is resolution. Digital recording has a set resolution, but so does analog. An analog recording on, say, vinyl, is limited by the material's ability to retain the shape of a sound wave. The resolution could be down to a few molecules, but really depends on the size of the tip of the needle that cuts the track, and the needle that follows the track to play it back. That is a limit that can be compared to digital resolution. Magnetic recording is limited to the fineness of the magnetic domains which depend on the size of the iron oxide crystals in the medium. The crystals are huge on a molecular scale, so magnetic recording may not be as fine as vinyl recording as far as waveform resolution is concerned. I just read that, very soon, hard drives will be able to store ten times their current linear density. I haven't run the numbers, yet, but this might approach the physical resolution of analog recording devices. I realize that a digital recording could be made at or near analog resolution, but the wave file would be enormous. Nearly the size of some hard drives. The proposed drives would be able to store that in the current fraction of the drive. So, does this mean that future samplers will be able to store digital samples that are indistinguishable from analog samples? Will CPUs and DSPs at that stage be able to handle that density of signal flow? What is the near future of samplers?

Addendum: 78 RPM records play back audio at about 43 inches per second. Wire plays back at 24 inches per second, so wire recording could be considered nearly twice the audible density of early vinyl. 33⅓ RPM records play back at about 20 inches per second, exceeding the audible density of wire. Highest quality magnetic tape recording is typically 30 inches per second, with consumer quality at 7½ inches per second. This does not take into consideration the audible quality of the various recordings, but it is doubtful that wire at standard speed could sound as good as reel to reel tape at high quality speed.

Later: I just had a thought, after randomly remembering that old ST:TNG episode with the Dyson sphere, in which Scotty saves his own life by storing himself in a transporter pattern buffer for eighty years by feeding the buffer back into itself in a continuous loop. I'm getting the inkling of an electronic circuit concept that involves capacitors and diodes to create a self-sustaining signal loop, much like booster technology in communication networks only in a discreet closed system. A circuit that analyzes the signal that it is passing through it in real time and replicates the signal to feed back into the start of the circuit, maintaining the signal indefinitely. With enough refinement, it could be the basis for a solid-state analog sampler.

Last edited by gridsleep on Fri Nov 16, 2012 11:35 pm, edited 1 time in total.

Interesting topic. Re: analog recording on hard disks - this might work, but would require great modification to the electronics of the drive. You would need a bias oscillator like a tape recorder to imprint any quality of analog signal on the disk.

I seem to recall a guitar delay/echo pedal that could record 2 seconds into a massive BBD line.

The Optigon and several Kimball home organs used printed paterns on disks (plastic on Optigan, glass in the Kimball)
read by a light and photocells.

Farther OT: There was a video projection device (for theaters) called the Ediphor. A rotating metal disk coated with a thin layer of oil was housed in a vacuum chamber. An electron gun - just like in a television CRT - projected an image onto the oil causing millions of tiny dimples. A powerful light source shown onto the disk also, and the reflected light was focused onto the screen. The dimples caused some of the light rays to miss the lens and created darker areas on the screen for a black and white picture. As the disk rotated out of the light, a knife edge smoothed the surface of the oil for the next frame.

Some ancient guitar Leslie simulator used a speaker and a mike rotating in a can of oil.

You could even wind a large coil of wire and lower the temperature to near absolute zero. The electrons (and the analog signal they formed) would be slowed down - maybe enough to get useful recording time.

When the wise man points to the stars, the fool looks at the finger.
- Confucius

Not exactly an "analog sampler", but the Akai AX-60 could get close to it....

With a MINI DIN cable connection and an AKAI S-612, S-900 or S-950 sampler, you can use samples as a second oscillator. Samples can be manipulated with the internal envelopes and sent through its analog filter.

You couldn't record onto hard disk, as I stated, because that instantly makes the sample digital. To be purely analog, the signal must remain analog along the entire signal path. Any recourse into digital storage would degrade the analog nature of the signal. See my addenda to the original post.

Hard disks DO record as a digital signal -- BUT the concept of recording an analog signal onto a magnetic media is much the same as a tape recorder. But as hard drives are made to accept a digital signal and record it as a series of 1s and 0s, you would need to scrap all the signal path electronics and design an analog system. Analog magnetic recording requires a bias oscillator to help overcome the magnetic media's "inertia" and give a more linear transfer.
There were (in the dim past) magnetic disk audio recorders.

When the wise man points to the stars, the fool looks at the finger.
- Confucius

I don't see samplers going anywhere beyond where they are now, and I don't see audio interfaces going beyond 24-bit. We are presently capable of making 32-bit resolution audio interfaces, but no one is doing it.

I like rhino's idea of an analog magnetic recording platter. It doesn't look as if anyone is manufacturing anything like that. The closest thing in modern parlance is a tape delay and even all those are simulated now. There has to be a way to suspend a signal discreetly within a circuit. Wait... Light? Laser? Infinite storage. A crystal. Wow, ZARDOZ flashback. But, that might be the way to do it. Store samples in laser in an infinitely refracting buffer. Light frequencies are well below audio, so even a tiny laser packet could store minutes of audio. With proper reflection and refraction, signal degradation might not even be a consideration. A photonic analog sampling synthesizer. Do away with electronics completely and just do it all with light. Wow. My brain is storming now.

Yes, analog samplers! I was all ready to list off all of the really cool optical sample playback devices of the early 20th century... and there were SEVERAL... as well as the Chamberlin, Mellotron, Optigan (NOT pronounced like "octagon," but pronounced like a combination of "optical" and "organ"), Orchestron, etc.

But really, those are analog ROMplers. An actual analog sampler would have to be able to RECORD and use sounds.

There was once a device like a Mellotron called a "Memotron" which used 8 track tapes and was able to record sounds for use, but I think only one was made.

More fascinating to me than an analog sampler would be an acoustic sampler. I have some ideas for an acoustic ROMpler, and I'm trying to imagine a means to create an acoustic sampler.

‎"I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question." -Charles Babbage
"Unity and Mediocrity are forever in bed together." -Zane W. http://www.youtube.com/automaticgainsay

Again, off OT but close:
Reproducing piano. Most simply made marks on the paper roll - which was punched later. There were models that puched the roll in real time, then could rewind and play back in the same instrument.
Maybe more of a mechanical sequencer?

Thinking more on this:
Maybe Edisons original phonograph?
Recorded and played back on the same simple machine.
Pitch control of playback.
If you left blank space between "samples", you could move the drum laterally to select.

When the wise man points to the stars, the fool looks at the finger.
- Confucius

gridsleep wrote:Has any sampler ever been based on wire recording? (The predecessor of magnetic tape.) I could imagine a device much like a piano with linear array of wires, but operating like the Mellotron with moving read/write heads, or perhaps the wires spooled endlessly on a drum. I'm rather surprised the Mellotron designers didn't go with this technology rather than the much more fragile magnetic tape. Tape recording is much higher density, at least with later technology, but wire is hardier and would last much longer under continuous use.

The heads would be moving at 24ips. Never mind the wear and tear on the wire, think about moving the heads around like that. Moving the wire in a mellotron type arrangement would work much better. The main issue however would be that wire recorders sound really really terrible. Nobody would want to use it.

Later: I just had a thought, after randomly remembering that old ST:TNG episode with the Dyson sphere, in which Scotty saves his own life by storing himself in a transporter pattern buffer for eighty years by feeding the buffer back into itself in a continuous loop. I'm getting the inkling of an electronic circuit concept that involves capacitors and diodes to create a self-sustaining signal loop, much like booster technology in communication networks only in a discreet closed system. A circuit that analyzes the signal that it is passing through it in real time and replicates the signal to feed back into the start of the circuit, maintaining the signal indefinitely. With enough refinement, it could be the basis for a solid-state analog sampler.

That's pretty much how a BBD delay works, recording a signal by passing it through a series of capacitors. The problem is that they don't store the voltage very well at all, and after even a second or so it's already degraded so much it doesn't sound much like the original signal that went in. It couldn't be used to make a sampler.

The reason we use digital samplers is because it's a method that works, really well. Why try to reinvent the wheel just so you can say 'this sampler is analogue'? Analogue doesn't mean better, I wish people would learn that. There's heaps of really terrible sounding analogue stuff out there.

This is almost as bad as people buying old prosumer 8 track recorders that they don't know how to set up and then recording onto them instead of their computer because it gives them a hard on to say that they recorded to analogue, even if it sounds like complete s**t.

Stab Frenzy wrote:The reason we use digital samplers is because it's a method that works, really well. Why try to reinvent the wheel just so you can say 'this sampler is analogue'? Analogue doesn't mean better, I wish people would learn that. There's heaps of really terrible sounding analogue stuff out there.

All true. I just like the idea of mechanically or electrically recorded sound. For me, at least, it's not about some sort of superiority (obviously, the fidelity is likely to be terrible), but rather the novelty.

‎"I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question." -Charles Babbage
"Unity and Mediocrity are forever in bed together." -Zane W. http://www.youtube.com/automaticgainsay